// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <cmath>
#include <memory>

#include "base/macros.h"
#include "base/memory/aligned_memory.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/stringize_macros.h"
#include "build/build_config.h"
#include "media/base/vector_math.h"
#include "media/base/vector_math_testing.h"
#include "testing/gtest/include/gtest/gtest.h"

using std::fill;

namespace media {

// Default test values.
static const float kScale = 0.5;
static const float kInputFillValue = 1.0;
static const float kOutputFillValue = 3.0;
static const int kVectorSize = 8192;

class VectorMathTest : public testing::Test {
 public:

  VectorMathTest() {
    // Initialize input and output vectors.
    input_vector_.reset(static_cast<float*>(base::AlignedAlloc(
        sizeof(float) * kVectorSize, vector_math::kRequiredAlignment)));
    output_vector_.reset(static_cast<float*>(base::AlignedAlloc(
        sizeof(float) * kVectorSize, vector_math::kRequiredAlignment)));
  }

  void FillTestVectors(float input, float output) {
    // Setup input and output vectors.
    fill(input_vector_.get(), input_vector_.get() + kVectorSize, input);
    fill(output_vector_.get(), output_vector_.get() + kVectorSize, output);
  }

  void VerifyOutput(float value) {
    for (int i = 0; i < kVectorSize; ++i)
      ASSERT_FLOAT_EQ(output_vector_[i], value);
  }

 protected:
  std::unique_ptr<float[], base::AlignedFreeDeleter> input_vector_;
  std::unique_ptr<float[], base::AlignedFreeDeleter> output_vector_;

  DISALLOW_COPY_AND_ASSIGN(VectorMathTest);
};

// Ensure each optimized vector_math::FMAC() method returns the same value.
TEST_F(VectorMathTest, FMAC) {
  static const float kResult = kInputFillValue * kScale + kOutputFillValue;

  {
    SCOPED_TRACE("FMAC");
    FillTestVectors(kInputFillValue, kOutputFillValue);
    vector_math::FMAC(
        input_vector_.get(), kScale, kVectorSize, output_vector_.get());
    VerifyOutput(kResult);
  }

  {
    SCOPED_TRACE("FMAC_C");
    FillTestVectors(kInputFillValue, kOutputFillValue);
    vector_math::FMAC_C(
        input_vector_.get(), kScale, kVectorSize, output_vector_.get());
    VerifyOutput(kResult);
  }

#if defined(ARCH_CPU_X86_FAMILY)
  {
    SCOPED_TRACE("FMAC_SSE");
    FillTestVectors(kInputFillValue, kOutputFillValue);
    vector_math::FMAC_SSE(
        input_vector_.get(), kScale, kVectorSize, output_vector_.get());
    VerifyOutput(kResult);
  }
#endif

#if defined(ARCH_CPU_ARM_FAMILY) && defined(USE_NEON)
  {
    SCOPED_TRACE("FMAC_NEON");
    FillTestVectors(kInputFillValue, kOutputFillValue);
    vector_math::FMAC_NEON(
        input_vector_.get(), kScale, kVectorSize, output_vector_.get());
    VerifyOutput(kResult);
  }
#endif
}

// Ensure each optimized vector_math::FMUL() method returns the same value.
TEST_F(VectorMathTest, FMUL) {
  static const float kResult = kInputFillValue * kScale;

  {
    SCOPED_TRACE("FMUL");
    FillTestVectors(kInputFillValue, kOutputFillValue);
    vector_math::FMUL(
        input_vector_.get(), kScale, kVectorSize, output_vector_.get());
    VerifyOutput(kResult);
  }

  {
    SCOPED_TRACE("FMUL_C");
    FillTestVectors(kInputFillValue, kOutputFillValue);
    vector_math::FMUL_C(
        input_vector_.get(), kScale, kVectorSize, output_vector_.get());
    VerifyOutput(kResult);
  }

#if defined(ARCH_CPU_X86_FAMILY)
  {
    SCOPED_TRACE("FMUL_SSE");
    FillTestVectors(kInputFillValue, kOutputFillValue);
    vector_math::FMUL_SSE(
        input_vector_.get(), kScale, kVectorSize, output_vector_.get());
    VerifyOutput(kResult);
  }
#endif

#if defined(ARCH_CPU_ARM_FAMILY) && defined(USE_NEON)
  {
    SCOPED_TRACE("FMUL_NEON");
    FillTestVectors(kInputFillValue, kOutputFillValue);
    vector_math::FMUL_NEON(
        input_vector_.get(), kScale, kVectorSize, output_vector_.get());
    VerifyOutput(kResult);
  }
#endif
}

TEST_F(VectorMathTest, Crossfade) {
  FillTestVectors(0, 1);
  vector_math::Crossfade(
      input_vector_.get(), kVectorSize, output_vector_.get());
  for (int i = 0; i < kVectorSize; ++i) {
    ASSERT_FLOAT_EQ(i / static_cast<float>(kVectorSize), output_vector_[i])
        << "i=" << i;
  }
}

class EWMATestScenario {
 public:
  EWMATestScenario(float initial_value, const float src[], int len,
                   float smoothing_factor)
      : initial_value_(initial_value),
        data_(static_cast<float*>(
            len == 0 ? NULL :
            base::AlignedAlloc(len * sizeof(float),
                               vector_math::kRequiredAlignment))),
        data_len_(len),
        smoothing_factor_(smoothing_factor),
        expected_final_avg_(initial_value),
        expected_max_(0.0f) {
    if (data_len_ > 0)
      memcpy(data_.get(), src, len * sizeof(float));
  }

  // Copy constructor and assignment operator for ::testing::Values(...).
  EWMATestScenario(const EWMATestScenario& other) { *this = other; }
  EWMATestScenario& operator=(const EWMATestScenario& other) {
    this->initial_value_ = other.initial_value_;
    this->smoothing_factor_ = other.smoothing_factor_;
    if (other.data_len_ == 0) {
      this->data_.reset();
    } else {
      this->data_.reset(static_cast<float*>(
        base::AlignedAlloc(other.data_len_ * sizeof(float),
                           vector_math::kRequiredAlignment)));
      memcpy(this->data_.get(), other.data_.get(),
             other.data_len_ * sizeof(float));
    }
    this->data_len_ = other.data_len_;
    this->expected_final_avg_ = other.expected_final_avg_;
    this->expected_max_ = other.expected_max_;
    return *this;
  }

  EWMATestScenario ScaledBy(float scale) const {
    EWMATestScenario result(*this);
    float* p = result.data_.get();
    float* const p_end = p + result.data_len_;
    for (; p < p_end; ++p)
      *p *= scale;
    return result;
  }

  EWMATestScenario WithImpulse(float value, int offset) const {
    EWMATestScenario result(*this);
    result.data_.get()[offset] = value;
    return result;
  }

  EWMATestScenario HasExpectedResult(float final_avg_value,
                                     float max_value) const {
    EWMATestScenario result(*this);
    result.expected_final_avg_ = final_avg_value;
    result.expected_max_ = max_value;
    return result;
  }

  void RunTest() const {
    {
      SCOPED_TRACE("EWMAAndMaxPower");
      const std::pair<float, float>& result = vector_math::EWMAAndMaxPower(
          initial_value_, data_.get(), data_len_, smoothing_factor_);
      EXPECT_NEAR(expected_final_avg_, result.first, 0.0000001f);
      EXPECT_NEAR(expected_max_, result.second, 0.0000001f);
    }

    {
      SCOPED_TRACE("EWMAAndMaxPower_C");
      const std::pair<float, float>& result = vector_math::EWMAAndMaxPower_C(
          initial_value_, data_.get(), data_len_, smoothing_factor_);
      EXPECT_NEAR(expected_final_avg_, result.first, 0.0000001f);
      EXPECT_NEAR(expected_max_, result.second, 0.0000001f);
    }

#if defined(ARCH_CPU_X86_FAMILY)
    {
      SCOPED_TRACE("EWMAAndMaxPower_SSE");
      const std::pair<float, float>& result = vector_math::EWMAAndMaxPower_SSE(
          initial_value_, data_.get(), data_len_, smoothing_factor_);
      EXPECT_NEAR(expected_final_avg_, result.first, 0.0000001f);
      EXPECT_NEAR(expected_max_, result.second, 0.0000001f);
    }
#endif

#if defined(ARCH_CPU_ARM_FAMILY) && defined(USE_NEON)
    {
      SCOPED_TRACE("EWMAAndMaxPower_NEON");
      const std::pair<float, float>& result = vector_math::EWMAAndMaxPower_NEON(
          initial_value_, data_.get(), data_len_, smoothing_factor_);
      EXPECT_NEAR(expected_final_avg_, result.first, 0.0000001f);
      EXPECT_NEAR(expected_max_, result.second, 0.0000001f);
    }
#endif
  }

 private:
  float initial_value_;
  std::unique_ptr<float, base::AlignedFreeDeleter> data_;
  int data_len_;
  float smoothing_factor_;
  float expected_final_avg_;
  float expected_max_;
};

typedef testing::TestWithParam<EWMATestScenario> VectorMathEWMAAndMaxPowerTest;

TEST_P(VectorMathEWMAAndMaxPowerTest, Correctness) {
  GetParam().RunTest();
}

static const float kZeros[] = {  // 32 zeros
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};

static const float kOnes[] = {  // 32 ones
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
};

static const float kCheckerboard[] = {  // 32 alternating 0, 1
  0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1,
  0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1
};

static const float kInverseCheckerboard[] = {  // 32 alternating 1, 0
  1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
  1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0
};

INSTANTIATE_TEST_CASE_P(
    Scenarios,
    VectorMathEWMAAndMaxPowerTest,
    ::testing::Values(
        // Zero-length input: Result should equal initial value.
        EWMATestScenario(0.0f, NULL, 0, 0.0f).HasExpectedResult(0.0f, 0.0f),
        EWMATestScenario(1.0f, NULL, 0, 0.0f).HasExpectedResult(1.0f, 0.0f),

        // Smoothing factor of zero: Samples have no effect on result.
        EWMATestScenario(0.0f, kOnes, 32, 0.0f).HasExpectedResult(0.0f, 1.0f),
        EWMATestScenario(1.0f, kZeros, 32, 0.0f).HasExpectedResult(1.0f, 0.0f),

        // Smothing factor of one: Result = last sample squared.
        EWMATestScenario(0.0f, kCheckerboard, 32, 1.0f)
            .ScaledBy(2.0f)
            .HasExpectedResult(4.0f, 4.0f),
        EWMATestScenario(1.0f, kInverseCheckerboard, 32, 1.0f)
            .ScaledBy(2.0f)
            .HasExpectedResult(0.0f, 4.0f),

        // Smoothing factor of 1/4, muted signal.
        EWMATestScenario(1.0f, kZeros, 1, 0.25f)
            .HasExpectedResult(std::pow(0.75f, 1.0f), 0.0f),
        EWMATestScenario(1.0f, kZeros, 2, 0.25f)
            .HasExpectedResult(std::pow(0.75f, 2.0f), 0.0f),
        EWMATestScenario(1.0f, kZeros, 3, 0.25f)
            .HasExpectedResult(std::pow(0.75f, 3.0f), 0.0f),
        EWMATestScenario(1.0f, kZeros, 12, 0.25f)
            .HasExpectedResult(std::pow(0.75f, 12.0f), 0.0f),
        EWMATestScenario(1.0f, kZeros, 13, 0.25f)
            .HasExpectedResult(std::pow(0.75f, 13.0f), 0.0f),
        EWMATestScenario(1.0f, kZeros, 14, 0.25f)
            .HasExpectedResult(std::pow(0.75f, 14.0f), 0.0f),
        EWMATestScenario(1.0f, kZeros, 15, 0.25f)
            .HasExpectedResult(std::pow(0.75f, 15.0f), 0.0f),

        // Smoothing factor of 1/4, constant full-amplitude signal.
        EWMATestScenario(0.0f, kOnes, 1, 0.25f).HasExpectedResult(0.25f, 1.0f),
        EWMATestScenario(0.0f, kOnes, 2, 0.25f)
            .HasExpectedResult(0.4375f, 1.0f),
        EWMATestScenario(0.0f, kOnes, 3, 0.25f)
            .HasExpectedResult(0.578125f, 1.0f),
        EWMATestScenario(0.0f, kOnes, 12, 0.25f)
            .HasExpectedResult(0.96832365f, 1.0f),
        EWMATestScenario(0.0f, kOnes, 13, 0.25f)
            .HasExpectedResult(0.97624274f, 1.0f),
        EWMATestScenario(0.0f, kOnes, 14, 0.25f)
            .HasExpectedResult(0.98218205f, 1.0f),
        EWMATestScenario(0.0f, kOnes, 15, 0.25f)
            .HasExpectedResult(0.98663654f, 1.0f),

        // Smoothing factor of 1/4, checkerboard signal.
        EWMATestScenario(0.0f, kCheckerboard, 1, 0.25f)
            .HasExpectedResult(0.0f, 0.0f),
        EWMATestScenario(0.0f, kCheckerboard, 2, 0.25f)
            .HasExpectedResult(0.25f, 1.0f),
        EWMATestScenario(0.0f, kCheckerboard, 3, 0.25f)
            .HasExpectedResult(0.1875f, 1.0f),
        EWMATestScenario(0.0f, kCheckerboard, 12, 0.25f)
            .HasExpectedResult(0.55332780f, 1.0f),
        EWMATestScenario(0.0f, kCheckerboard, 13, 0.25f)
            .HasExpectedResult(0.41499585f, 1.0f),
        EWMATestScenario(0.0f, kCheckerboard, 14, 0.25f)
            .HasExpectedResult(0.56124689f, 1.0f),
        EWMATestScenario(0.0f, kCheckerboard, 15, 0.25f)
            .HasExpectedResult(0.42093517f, 1.0f),

        // Smoothing factor of 1/4, inverse checkerboard signal.
        EWMATestScenario(0.0f, kInverseCheckerboard, 1, 0.25f)
            .HasExpectedResult(0.25f, 1.0f),
        EWMATestScenario(0.0f, kInverseCheckerboard, 2, 0.25f)
            .HasExpectedResult(0.1875f, 1.0f),
        EWMATestScenario(0.0f, kInverseCheckerboard, 3, 0.25f)
            .HasExpectedResult(0.390625f, 1.0f),
        EWMATestScenario(0.0f, kInverseCheckerboard, 12, 0.25f)
            .HasExpectedResult(0.41499585f, 1.0f),
        EWMATestScenario(0.0f, kInverseCheckerboard, 13, 0.25f)
            .HasExpectedResult(0.56124689f, 1.0f),
        EWMATestScenario(0.0f, kInverseCheckerboard, 14, 0.25f)
            .HasExpectedResult(0.42093517f, 1.0f),
        EWMATestScenario(0.0f, kInverseCheckerboard, 15, 0.25f)
            .HasExpectedResult(0.56570137f, 1.0f),

        // Smoothing factor of 1/4, impluse signal.
        EWMATestScenario(0.0f, kZeros, 3, 0.25f)
            .WithImpulse(2.0f, 0)
            .HasExpectedResult(0.562500f, 4.0f),
        EWMATestScenario(0.0f, kZeros, 3, 0.25f)
            .WithImpulse(2.0f, 1)
            .HasExpectedResult(0.75f, 4.0f),
        EWMATestScenario(0.0f, kZeros, 3, 0.25f)
            .WithImpulse(2.0f, 2)
            .HasExpectedResult(1.0f, 4.0f),
        EWMATestScenario(0.0f, kZeros, 32, 0.25f)
            .WithImpulse(2.0f, 0)
            .HasExpectedResult(0.00013394f, 4.0f),
        EWMATestScenario(0.0f, kZeros, 32, 0.25f)
            .WithImpulse(2.0f, 1)
            .HasExpectedResult(0.00017858f, 4.0f),
        EWMATestScenario(0.0f, kZeros, 32, 0.25f)
            .WithImpulse(2.0f, 2)
            .HasExpectedResult(0.00023811f, 4.0f),
        EWMATestScenario(0.0f, kZeros, 32, 0.25f)
            .WithImpulse(2.0f, 3)
            .HasExpectedResult(0.00031748f, 4.0f)));

}  // namespace media